1. Field of the Invention
The invention relates to turnover mechanisms used in association with conveyers for the purpose of turning over individual articles carried on the conveyer and, more particularly, to such a device which utilizes a simple synchronized gear system for controlling the rates of rotations of a pair of counter rotating carrier members.
2. Description of the Relevant Prior Art
Mechanisms designed for turning over articles being advanced along a production path have long been known in the prior art. Moreover, the employment of counter rotating arms to effect the turnover is also known. For examples of U.S. Patents which disclose turnover devices employing counter rotating arms, see for example U.S. Pat. Nos. 3,552,538; 3,780,882; and 4,533,291. The counter rotating arms disclosed in the above listed patents are, typically, initially disposed horizontally, with the respective axes of rotation parallel and spaced apart from each other. An article is carried by a conveyer onto an upper surface of one of the pair of the counter rotating arms. The pair of arms are caused to rotate towards each other until they are disposed in parallel, spaced apart vertical planes. To help effectuate the turnover, the parallel planes may be slightly inclined from the vertical, as shown in U.S. Pat. No. 3,780,882. The article is thereby transferred to the second of the pair of counter rotating arms. The arms are then caused to rotate back to their substantially horizontal, initial positions. At that point the article will lie atop an upper surface of the conveyor.
While the devices disclosed in these patents are affective in turning an article over, they are complicated and, hence, relatively expensive mechanisms for controlling and coordinating the relative rates of counter rotation of the pair of arms. In U.S. Pat. No. 3,780,882, the counter rotating arms are independently pivoted by hydraulic actuators. In U.S. Pat. No. 3,581,910, counter rotating arms are mounted on separate, rotatable shafts where they are connected to inboard arms so constructed and located to cause the inboard edge of the article to drop down below a receiving position. Additional arms are connected to the outboard end of the counter rotating arms. In U.S. Pat. No. 4,533,291, the counter rotating arms are connected at one end to attachment plates upon which the article is placed and at the other end to arm holders. The arm holders are, in turn, rotatably supported by first and second carriers. First and second crank drive mechanisms are associated with the carriers and rock the counter rotating arms in an inlet-outlet direction when the carriers are moved in that direction. Carrier drive means are provided for driving the first and second carriers simultaneously in opposite directions so that they may approach to each other and separate from each other.
It would be desirable to provide a turnover device useful in a production line which has relatively few moving parts, and is inexpensive and quiet.
It would also be desirable to provide such a devise which has straight-through capabilities and a low profile.
It would also be highly desirable to provide such a devise which is useful for turning over such mass produced, relatively flat and heavy articles such as tire and wheel assemblies.